Walbro MDC-3 Carburetor Question

[Alaskan Stihl]

Question: After the rebuild of a Walbro MDC-3 Carburetor, I attempted a Pressure test via the Fuel intake line…and it failed (did not hold 7psi). In fact, it bled down rather quickly.

Question: Is this carburetor capable of enduring a pressure test, or is one of those Walbro models that is designed in a way that won’t allow pressure to build up? *Note that I did screw in the H&L Idle Screws (snugly) and it still failed. Did I miss something?

 

[Alaskan Stihl]

All:

Nevermind…my mistake…I figured it out. Problem is that I was using a older Gasket Set and they were a bit hard (not the diaphragms, but the gaskets themselves). I was able to tighten them up a smidge and applied a touch of heat (hairdryer) and Tada…it want to hold pressure now (7psi).

I will run a couple more tests. One other thing that leaves me in a bind….is how does the MDC Walbro “W” Lever Gauge suppose to work on a MDC Carburetor? The inscribe on the tool is on the inner leg of the tool which leads me to believe it must be positioned in such a way that is different than just leveling it out along the edge. I will do a little more research and probably just make sure it is level across (unless someone knows how the tool is suppose to work)?